Preparation of triaminoguanidine compounds from dicyandiamide



United States Patent Ofilice 3,285,958 Patented Nov. 15, 1966 The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to triaminoguanidine (hereinafter referred to as TAG) and salts thereof and more particularly concerns unique and improved processes for their preparation.

In the past, TAG had been prepared by Stolle and Krauch by reacting dicyandiamide (hereinafter referred to as DCDA) and hydrazine hydrate at 40 C. for about 8 hours. The low yield product isolated was identified as the tribenzylidene hydrochloride derivative and data concerned therewith are shown in the table, Experiment No. 1. When the reaction temperature was raised to 110 C. (Exp. No. 2) and the reaction time decreased to about 5 /2 hours, other conditions remaining generally the same, no triaminoguanidine nitrate (hereinafter referred to as TAGN) was formed.

TAGN may be prepared by the aqueous fusion of calcium cyanamide and hydrazine nitrate. If DCDA disproportionates into cyanamide in accordance with the reaction it would appear likely that hydrazine nitrate would react and form TAGN as in the aqueous fusion of calcium cyanamide. When DCDA was used under similar conditions as the calcium cyanamide fusion method, no TAGN was formed as shown in the table, Experiment No. 3.

Since TAG compounds are finding widespread application in vital rocket and artillery components as well as in explosives, des-oxidants, organic intermediates, etc., it would be advantageous if improved processes for their preparation could be developed.

It is therefore a broad object of this invention to provide processes for preparing TAG compounds.

Another object of the invention is .to provide high purity, good yield TAG compounds which involve improved processes.

Other and further objects of the invention will be apparent to those skilled in the art upon study of this disclosure.

It is known that TAG free base decomposes rapidly in moist air or in an aqueous medium. Hence, it is necessary to make the salt of the free base more stable during the reaction in order to decrease its tendency toward decomposition which can readily be accomplished by reacting a mixture of hydrazine nitrate and hydrazine hydrate with DCDA. A 54% yield of TAGN was obtained and the data are shown in Table I, Experiment No. 4. As a result thereof the hydrazine nitrate was increased in amount from to 200% while the hydrazine hydrate was maintained constant. The stoichiometric relationship of DCDA to hydrazine adduct was taken as 1 to 6 in accordance with the following equation: NH C= (NH)NH-CN+ 6N H -X 2 TAG'X+4NH -X where X is the acid component.

The stoichiometric amount of hydrazine nitrate was based on a 1:6 molar ratio of DCDA to hydrazine nitrate to yield the required amount of TAGN. Similarly, concentrations in excess of this ratio were used. These reactions were carried out at -90 C. for about 3 /2 hours. The result-s are tabulated in Experiments No. 5 through 9 inclusive. Yields were based on 1:1 molar ratios of DCDA to TAGN since it became evident that under the conditions of the reaction, disproportionation of DCDA did not yield two moles of cyanamide as predicted. Except for Experiment No. 5, the yield of TAGN was fairly constant and did not depend on a large excess of hydrazine nitrate as in the aqueous fusion of calcium cyanamide method or hydrazine nitrate method.

As a result of these experiments, the amount of hydrazine nitrate was reduced to equimolar proportions to DCDA. Only a 25% excess of hydrazine nitrate was used to insure complete conversion of the free base to the nitrate salt. A yield of 87.7% TAGN was now obtained and the results are listed in Table 1, Experiment No. 10.

In order to determine the concentration of hydrazine hydrate for optimum yields of TAGN, the molar ratio of DCDA to hydrazine hydrate was reduced as shown in Experiment-s No. 11 and 12. These results indicate that at least a 1:3 molar ratio of DCDA to hydrazine hydrate was needed for optimum yields of TAGN.

Again, in determining the effect of temperature upon the yield of TAGN, Stolles 40 C. reaction temperature condition was performed and then compared to my experiment carried out at 80-90 C. (Experiments No. 13 and No. 6, Table I). The yield at the lower temperature was only 60% compared to 79% at the higher temperature. Stolle claims that at a higher temperature (6070 C.) and a large excess of hydrazine hydrate (1 mole of DCDA to 2.5 moles of hydrazine hydrate), the best yield of guanazole is obtained. In my modified procedure, the best yield of TAGN was obtained at 8090 C. with a 1:425 molar ratio of DCDA to hydrazine adduct. Upon increasing the reaction temperature from 80-90 C. to 110-415 C. there was no change in yield of TAGN as shown in Table I, Experiments No. 4 and 5.

The effect of reaction time was also determined under one set of conditions as shown in Experiments No. 9 and 14. In one hour, a 73% yield of TAGN was obtained as compared to a 78% yield for a reaction time of 3% hours.

EXAMPLE NO. I

A typical procedure for the preparation of TAGN from DCDA is given below:

Chemicals 16.8 g. (0.2 mole) DCDA 23.75 g. (0.25 mole) hydrazine nitrate (25 excess) 35.3 g. (0.6 mole) hydrazine hydrate solution) Procedure In a 200 ml. 3-necked, round bottom flask, fitted with a mechanical stirrer, the DCDA is added to the solution of hydrazine nitrate in hydrazine hydrate. The mixture is heated at 85-90 C. by means of an oil bath for about 3.5 hours. 110 ml. of water is then added. The mixture is heated until the solid dissolves. The solution is quickly transferred to beaker and chilled in an ice bath. The product is filtered, washed with cold water and dried in the oven at about C. or in a vacuum desiccator over sulfuric acid. The yield of material is 87.7% (M.P. 215- 216 C.). The minimum molar ratios of DCDA to hydrazine nitrate, and hydrazine hydrate are of the order of 1 to 1.25 to 3 respectively.

EXAMPLE NO. 2.PREPARATION OF TRIAMINO- GUANIDINE NITRATE Chemicals 16.8 g.'(0.2 mole) DCDA 23.75 g. (0.25 mole) hydrazine nitrate (25% excess) 47.1 g. (0.8 mole) hydrazine hydrate (85% solution) Procedure 16.8 g. (0.2 mole) DCDA The DCDA is added to a vigorously Stirred Solution 30.8 g. (0.25 mole) unsymmetrical dimethyl hydrazine of the hydrazine nitrate in hydrazine hydrate. The mixit t ture is heated for 3.5 hours at 85-90 C. followed by the 36 (0,60 ole) unsymmetrical dimethyl hydrazine addition of 110 ml. of water. The mixture is heated to Procedure dissolve the solid material and the solution is quickly transferred to a beakerand chilled .in an ice bath. The- ...-The a'bove chemicals are heated at 85-90? C w th stir- TAGN is filtered, washed with ice cold water and dried ring for 3.5 hours. 110 ml. of water is added and the at 100 C. The yield of product is 87.7%. mixture heated once more to effect solution. The solution is then quickly transferred to a beaker and chilled. Y g z fi ggfi The product is filtered, washed with cold water, and

dried by standard procedure. EXAMPLE NO. 6.-PREPARATION OF TRIS- 16.8 g. (0.2 mole) DCDA (PHENYLAMINO) GUANIDINE NITRATE 34.2 g. (0.5 mole) hydrazine hydrochloride excess) (CH H NHNH) C=NNHC H -HNO 47.0 g. (0.8 mole) hydrazine hydrate (85% solution) 25 Chemicals Procedm 16.8 g. 0.2 mole) DCDA The above mixture is heated at 8090 C. with stirring 42.8 g. (0.25 mole) phenyl hydrazine nitrate for 1.5 hours. 100 ml. of water is added and the mix- 64,8 g. (0.6 mole) phenyl hydrazine ture is heated to effect solution. The solution is then P Ocedu e quickly poured into a beaker and chilled. The product r r is filtered, washed with ice cold water, and dried at 100 The procedure is the same as in Example No. 5.

TABLE I Dicyan- Hydrazine Excess Hydrazlne Reaction Reaction Yield of Experiment diamide Nitrate Hydrazine Hydrate Time Tempera- TAGN Remarks N o. (Moles) (Moles) Nitrate (Moles) (Hours) ture 0.) (Percent) (Percent) 0. 238 60 8.0 40 6. 6 Reaction Conditions Reported by Stolle. 0. 20 1 0. 60+ 5. 5 110 Nil Higher Temperature than Exp. N o. 1. 0.10 1.9 225.0 2.0 130-135 Nil Same Conditions as CaGN, Fusion 0. 20 0.44 10.0 0. 88+ 2.0 110-115 54.0 or rr alr e'with Exp. No. 5 101' Temp. 0.10 0.22 10.0 0.40 2.0 85-90 54.0 Efreoi oiH drazine Nitrate. 0. 10 0. 25 25. 0 0. 40 3. 5 80-90 79. 0 Do. 0.10 0.30 50.0 0.40 3.5 80-90 784 Do. 0. 10 0. 40 100. 0 0. 40 3. 5 80-90 76. 0 Do. 0. 10 0. 00 200. 0 0. 40 3. 5 80-90 78. 0 Do. 0.20 0.25 25.0 0.80 3.5 80-90 87.7 Molar ratio of DCDA to hydrazine nitrate to hydrazine hydrate 1:1.25z4. 0.20 0.25 25.0 0. 00 3.5 -90 87.7 Molar ratio 1;1.25=3. I 0. 20 0.25 25.0 0.40 3.5 85-90 70.5 Molar ratio 1:1.2512. 0.10 0.25 25.0 0.40 8.0 60.0 Eiligect oNt T6e)mperature (compare with X 0. 0.10 0. 60 200.0 0. 1. 0 85-90 73. 0 Efiec t oi Reaction Time (compare with Exp. No. 9).

1 10% Excess.

C. The yield of TAG-HCI is 89% (M.P. 240 un- The success of my processes resides principally in the corrected). inclusion of hydrazine nitrate in the aforementioned re- EXAMPLE NO. 4.--PREPARATION OF TRIS- f fi g ff i 55 5 fiaracterfed i i (METHYL AMINO) GUANIDINE NITRATE p y. y razine n1 ra e prov1 es e reac ion w1 t e NHNH) NNHCH 'HNO hydrazine adduct and more importantly, prevents the de- 3 PC: 3 3 composition of the TAG base by forming the more stable Chemicals 65 nitrate salt.

My process can be used to prepare other TAG comgmole) DCDA ponents by the use of hydrazine sulfate, chloride, per- 8' mole) monomethyl hydfazllle filtrate chlorate, hydrazoate, toluenesulfonate, oxalate and other 27.0 g. (.6 mole) monomethyl hydrazine organic acids Procedure It is also possible to substitute other hydrazinium components such as monoalkyl and unsymmetrical dialkyl The above mixture is heated at -90" C. w1th stirring hydrazines as well as their counterparts. More spefor 3.5 hours. rnl. of water 1s then added and the cifically, monomethyl hydrazine, unsymmetrical dimethyl mixture heated to dissolve the solid. The solution is hydrazine, phenyl hydrazine and methyl phenyl hydrazine quickly poured into a beaker and chllled. The product 75 have been found to work admirably well.

My process is also more economical than the calcium cyanamide fusion method as shown by the following data:

I claim:

1. A process for preparing triaminogdianidine compounds by reacting dicyandiamide with a compound selected from the group consisting of hydrazine nitrate and hydrazine hydrate; hydrazine hydrochloride and hydrazine hydrate; monomethyl hydrazine nitrate and monomethyl hydrazine; unsymmetrical dimethyl hydrazine nitrate and unsymmetrical dimethyl hydrazine; and phenyl hydrazine nitrate and phenyl hydrazine.

2. A process for preparing triaminoguanidine nitrate compounds by reacting 16.8 g. dicyandiamide, 23.75 g. hydrazine nitrate and an 85% solution of 35.3 to 47.1 g. hydrazine hydrate, heating the reactants to 85-90 C. for almost 3 /2 hours, adding about 110 ml. of Water to the heated reactants, further heating the diluted reactants until solid dissolves to form a solution, chilling the solution and filtering, washing and drying the triaminognanidine nitrate.

3. A process for preparing triaminoguanidine hydrochloride by reacting 16.8 g. dicyandiamide, 34.2 g. hydrazine hydrochloride and an 85% solution of 47.0 g. hydrazine hydrate, heating the reactants to 8090 C. for 1 /2 hours, adding about 100 ml. of water to the 6 heated reactants, heating the diluted reactants to form a solution, chilling the solution and filtering, washing and drying the triaminoguanidine hydrochloride.

4. A process for preparing tris(methylamino) guanidine nitrate by reacting 16.8 g. dicyandiamide, 27.3 g. monomethyl hydrazine nitrate and 27.0 monomethyl hydrazine, heating the reactants to 90 C. for 3 /2 hours, adding 110 ml. of water to the heated reactants, heating the diluted reactants to form a solution, chilling the solution and filtering, Washing and drying the tris(methylamino) gnanidine nitrate.

5. A process for preparing tris(dirnethylamino) guanidine nitrate by reacting 16.8 g. dicyandiamide, 30.8 g. unsymmetrical dimethyl hydrazine nitrate and 36.0 g. unsymmetrical dimethyl hydrazine, heating the reactants to 8590 C. for 3 /2 hours, adding 110 ml. of Water to the heated reactants, heating the diluted reactants to form a solution, chilling the solution and filtering, washing and drying the tris(dimethylamino) gnanidine nit-rate.

6. A process for preparing tris(phenylamino) guanidine nitrate by reacting 16.8 g. dicyandiamide, 42.8 g. phenyl hydrazine nitrate and 64.8 g. phenyl hydrazine, heating the reactants to 80-90" C. for 1 /2 hours, adding about ml. of Water to the heated reactants, heating the diluted reactants to form a solution, filtering, washing and drying the tris(phenylamino) gnanidine nitrate.

References Cited by the Examiner UNITED STATES PATENTS 7/ 1960 Habernickel 260-551 

1. A PROCESS FOR PREPARING TEIAMINOGUANIDINE COMPOUNDS BY REACTING DICYANDIAMIDE WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF HYDRAZINE NITRATE AND HYDRAZINE HYDRATE; HYDRAZINE HYDROCHHLORIDE AND HYDRAZINE HHYDRATE; MONOMETHYL HYDRAZINE NITRATE AND MONOMETHYL HYDRAZINE; UNSYMMETRICAL DIMETHYL HYDRAZINE NITRATE AND UNSYMMETRICAL DIMETHYL HYDRAZINE; AND PHENYL HYDRAZINE NITRATE AND PHENYL HYDRAZINE. 